Drain traps such as described above are installed, for example, in drainage paths which discharge liquid such as drain water of air conditioners to drainage basins. Being equipped with a normally-closed valve disc which floats up to allow liquid to flow from the storage space to the discharge space when the liquid in the storage space reaches or exceeds a set amount, such a drain trap prevents backflow of contaminated air and bad odors using a water sealing action of the liquid stored in the storage space and closing action of the valve disc.
Conventional drain traps include one which comprises a ball-shaped valve disc; a tubular valve disc guide tube which guides movements of the valve disc; a partition which, being constructed integrally with a main body, partitions inner space of the main body into storage space and discharge space; and a valve seat which, being constructed integrally with the partition, catches and supports the valve disc, in which the valve disc guide tube is configured to be insertable into the inner space of the main body (see, for example, Patent Document 1).
In the drain trap described in Patent Document 1, the partition is constituted of a plate-like body which partitions the inner space of the main body into L-shaped storage space and rectangular discharge space when viewed from a side. The partition which is a plate-like body is constructed integrally with the main body, extending inward from a side wall of the main body. The valve seat is installed in such a location on the partition that corresponds to an opening which communicates the storage space and discharge space.
[Patent Document 1]: Japanese U.M. Application “kokai” No. 52-3057